1. Statement of the Technical Field
The present invention relates to the field of collaborative computing and more particularly to instant messaging and chat systems.
2. Description of the Related Art
Real time communications systems provide a substantial enhancement over more traditional, asynchronous communications systems. Electronic mail delivery systems, the prototypical asynchronous communications systems, in its time represented a giant leap forward in respect to global interpersonal communications. Prior to electronic mail, individuals primarily communicated via telephone, facsimile and post. With electronic mail, however, individuals expect near instant delivery of text, and even imagery, audio and video, without incurring the delay typical of the postal system, or the expense associated with telephony and fax technologies.
Despite the ubiquity of electronic mail, asynchronous communications systems lack several elements common in the realm of real time communications systems. In particular, the seemingly instant delivery of a message cannot be experienced in the world of electronic mail. In an real-time society, the minor latencies associated with electronic mail often cannot be suitable for the task at hand where a real-time conversation will be required in addressing a problem or performing a collaborative task. More importantly, often the feel and nature of a “conversation” as it is known to human beings only can be approximated through real time communications where the participants to a conversation feel the spontaneity of an exchange of ideas, much as is the case in a live, face-to-face conversation.
Instant messaging software is becoming increasingly popular as a tool for computer-mediated communication. Conventional chat systems are synchronous in nature in that participants converse with one another in real-time or nearly real-time, by composing and transmitting messages to one another when the participants are online and able to respond. Chat software typically features two “panes”: one pane for composing, editing and transmitting a message, and another pane for displaying a running record of the conversation. Generally, participants “take turns” sending messages, which appear to all participants as a linear sequence in the display pane; all participants see the same stream of messages. As more messages are exchanged in a chat system, the record of the conversation can become longer, causing the record pane to scroll out of the visible display area thus necessitating the use of scrollbars to fully access the entire record.
Despite the popularity of instant messaging systems, there are some well-recognized drawbacks. One drawback includes the general lack of some floor-control mechanisms so that participants to a chat need not compete with one another to have the “next turn” and to contribute to the single “leading edge” of the conversation. Another drawback includes the incompatibility of the serial nature of “turns” with the semantically parallel nature of an underlying conversation. For example, participants to a chat can discuss more than one topic concurrently, and comments relating to the various topics can appear interspersed in a serial record of the chat. Moreover, in the course of a series of messages regarding a single topic, a chat participant can respond to an earlier comment on an unrelated theme. As a result, the serial record easily can become confusing and ambiguous.
Some research systems have been designed to address some of these concerns. “Threaded Text Chat”, for instance, aims to improve upon conventional chat by providing a threaded discussion tree with which participants can synchronously interact. “Turns” in a threaded text chat are explicit responses linked to previous comments while message indentations indicate the tree structure of the conversation. The threaded, real-time tree approach enjoys a few advantages over conventional chat systems. First, multiple coherent conversations can be conducted simultaneously. Second, multiple users can take turns at the same time. Third, users can collapse branches of the conversation they no longer find relevant. And finally, a conversation transcript is less prone to ambiguity.
Nevertheless, synchronous threaded chat systems introduce a new set of problems. Most notably, there is no one “leading edge” or point of focus for the conversation which can cause users to have difficulty tracking new messages. In some cases, new responses even can be added to distant branches of the threaded discussion tree, particularly where the distant branches have already scrolled out of view of the end user. When a new response is added to a distant branch of the threaded discussion tree, there is no obvious way to bring the new response to the attention of the end user.